Ridge roof beam

ABSTRACT

A ridge roof beam for a modular housing unit. The beam includes an elongated plywood web and a pair of elongated wood flanges extending adjacent and parallel to opposite edge margins of the web and secured in face-to-face relation to one face of the web. The web and flanges are each constructed of elongated wood sections bonded together in end-to-end relation. Finger grooves extending along adjacent end edges of the sections interlock to form a secure joint therebetween.

tlnited States Patent [1 1 Bowling [4 1 Feb. 12,1974

[ RIDGE ROOF BEAM [75] Inventor: J. Dennis Bowling, Battleground,

Wash.

[73] Assignee: I-Iearin Forest Industries, Beaverton,

Oreg.

[22] Filed: Aug. 7, 1972 [21] Appl. No.: 278,548

[52] -U.S. Cl 52/79, 52/90, 52/593, 52/726 [51] Int. Cl. E04c 3/00 [58]Field of Search. 52/729, 726, 730, 79, 90, 642, 52/92, 93, 593; 287/2092TG [56] References Cited UNITED STATES PATENTS 2,334,113 11/1943Malarkey 287/2092 T 2,287,229 6/1942 Carpenter..... 3,170,198 2/1965Snider 52/642 FOREIGN PATENTS OR APPLICATIONS 843,330 3/1939 France287/2092 T 897,622 7/1949 Germany 52/79 111,712 9/1944 Sweden 52/729OTHER PUBLICATIONS Plywood of the World, by Andrew D. Wood, pp. 423-426,published by Johnston & Bacon Ltd., 1963, TS/870/W6.

Primary Examiner-John E. Murtagh Attorney, Agent, or FirmKolisch,Hartwell & Dickinson [57] ABSTRACT A ridge roof beam for a modularhousing unit. The beam includes an elongated plywood web and a pair ofelongated wood flanges extending adjacent and parallel to opposite edgemargins of the web and secured in face-to-face relation to one face ofthe web. The web and flanges are each constructed of elongated woodsections bonded together in end-to-end relation. Finger groovesextending along adjacent end edges of the sections interlock to form asecure joint therebetween.

11 Claims, 5 Drawing Figures RIDGE ROOF BEAM BACKGROUND AND SUMMARY OFTHE INVENTION This invention relates to a beam, such as may be used asthe ridge roof beam of a housing unit, and more particularly to such abeam which is constructed of multiple end-joined wood sections.

In the construction of modular housing units, which generally aremanufactured at a central location and then transported to a desiredsite, it is desirable to construct the housing unit as light in weightand at as low a cost as possible, while still maintaining sufficientstructural rigidity. A problem that has existed in the past is theprovision of a ridge roof beam extending lengthwise of a housing unitwhich provides all of these desirable characteristics, i.e., lightweight, structural rigidity, and low cost.

In the past, various types of ridge roof beams have been devised usingplywood and/or lumber. Where plywood has been used previously, the beamsgenerally have taken the form of a number of plywood sheets havingsquare cut end edges which are merely laid together in end-to-endrelation to form a long section, with a similarly-formed section gluedin face-to-face contact wtih the first-mentioned section. The jointsbetween adjacent sheets in the one section had to be offsetlongitudinally of the beam from joints between adjacent sheets in theother section to provide even minimum strength for the beam. Further,such beams had to be relatively heavy to provide sufficient spanstrength.

A general object of the invention is to provide a novel flanged beamwhich may be used as a ridge roof beam in a modular housing unit, whichbeam has excellent strength characteristics for spanning long distanceswhile being relatively light weight and inexpensively constructed.

More specifically, an object is to provide a beam which has a webconstructed of a plurality of elongated plywood web sections bondedtogether in end-to-end relation at finger joints along adjacent sets ofends of the sections, and flanges secured to one face of the web andextending adjacent and parallel to opposite longitudinal margins of theweb. The flanges may be constructed of plywood sections bonded inend-to-end relation at finger joints therebetween. The bonding togetherof sections in the beam through finger joints produces good continuousstrength throughout the length of the beam, and the flanges securedadjacent opposite edge margins of the web provide good load bearingstrength with minimal weight.

DRAWINGS These and other objects and advantages will become more fullyapparent as the following description is read in conjunction with thedrawings, wherein:

FIG. 1 is a perspective view of a pair of mating, complemetary modularhousing units which may be joined together to form an integralstructure, each unit employing a ridge roof beam according to theinvention;

FIG. 2 is an enlarged perspective view of a section of a ridge roof beamseparated from its associated housing unit, with portions of the beambroken away;

FIG. 3 is an enlarged cross-sectional view taken generally along theline 3--3 in FIG. 2 of a finger joint between adjacent sections in thebeam;

FIG. 4 is an enlarged view taken generally along the line 4--4 in FIG.1; and

FIG. 5 is a view of a modified version of the invention.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings, andfirst more specifically to FIG. 1, at 10, 12 are illustrated generally apair of modular housing units. The units are illustrated spaced apartwith a pair of mating, complementary sides of the units facing eachother. The facing sides of the two units may be moved into engagementwith each other and secured together, with the combined units forming anintegral structure.

Each unit has an elongated ridge roof beam 16 extending longitudinallyalong one of its sides for supporting the roof structure of the unit.Referring to FIG. 2, where a portion of a beam 16 is illustrated indetail, it will be seen that the beam includes an elongated web 20 and apair of spaced-apart elongated flanges 22, 24. The flanges are secured,as by gluing, in face-to-face relation to one face of the web and extendparallel to and adjacent opposite longitudinal edge margins of the web.

Web 20 is constructed of a plurality of elongated plywood web sections,such as those illustrated partially at 28, 30, joined together inend-to-end relationship. Each section is illustrated as being made of5-ply plywood (as seen in FIG. 3), although it will be understood thatplywood of a different number of plies also may be used. The veneersheets which are glued together along glue lines between theircontiguous faces to form section 28 are indicated in FIG. 3 at 28a, 28b,28c, 28d, 28e. Veneer sheets 28a, 28e forming the outer, or opposite,face plies of the web section are disposed with the grain thereofextending generally in a direction longitudinally of the beam and, as iscommon for plywood sheets, these face plies extend the full length oftheir associated section.

Housing units as illustrated at l0, 12 may be 50 feet or more in lengthand beam 16 may extend the full length of the unit. Plywood generally isproduced in sheet 8 or 10 feet in length. Thus it may require five ormore end-joined web sections to form the web for such beam.

As is seen in the broken-away portion of FIG. 2 and in thecross-sectional view of FIG. 3, adjacent end edges of web sections 28,30 have mating, complementary grooves extending lengthwise of the edges.Referring specifically to FIG. 3, each grooved end edge provides a pairof fingers, such as those illustrated generally at 32, 34, on panel 28,extending between opposite longitudinal edge margins of the web sectionand paralleling the faces of the web section. The grooves providedbetween these fingers receive similar fingers on an adjacent section.

The fingers in the end edge of a panel are formed by making a out alongthe edge of the section to produce a first surface 36a spaced inwardlyfrom the end edge of the section extending inwardly from an outer faceof outer sheet 28a at a substantial angle relative thereto andterminating at an inner edge intermediate the faces of sheet 280. Asecond surface 36b extends from the inner edge of the first surface in aplane inclined at a low angle away from the outer surface of the sheet,across a glue line between veneer sheets 28a, 28b, to the end edge ofthe section. A third surface 38c, disposed toward the other face of thesection from second surface 36b, extends away from the end edge of thesection in a plane inclined at a low angle, across the glue line betweensheets 28b, 280, to an inner end spaced from the end edge of the sheet.A fourth surface 36d extends substantially parallel to second surface36b from the inner end of third surface 360 to the end edge of thesection, with the fourth surface intersecting the end edge in a regionintermediate the faces of outer veneer sheet 280. A fifth surface 36eextends at a substantial angle relative to the outer face of the sectionbetween fourth surface 36d and the outer face of the veneer sheet.

The grooved end of section 30 has a configuration similar to thatdescribed for section 28 and, in fact, may be formed with the samecutter head. Section 30, as illustrated in FIG. 3, is merely turned overfrom the position of section 28 so that their grooved ends arecomplementary.

Sections 28, 30 are joined together along their adjacent grooved edgesby applying adhesive therebetween, and forcing them longitudinally intoone another with the fingers on the adjacent edges interlocking. Heatand pressure may be applied against the outer surfaces of the jointduring curing of the adhesive to assure that a secure bond is obtainedbetween the sections. Surfaces 36a, 36e extending at sharp anglesinwardly from the outer surfaces of the face plies assure that therewill be no splinter edges lying along the outer faces of the sections.

Each of flanges 22, 24 as illustrated are formed of a plurality ofelongated plywood flange sections. Portions of a pair of flange sections38, 40 for flange 22 and portions of a pair of flange sections 42, 44for flange 24 are illustrated in FIG. 2. The flange sections are joinedtogether in end-to-end relationship through interlocking adhesivelybonded finger joints formed by grooves at their adjacent sets of ends,similar to those described above for the interlocking finger jointsbetween the web sections. The flanges have widths which are less thanhalf the width of the web section and are secured adjacent oppositelongitudinal edge margins of web 20. The flange sections illustrated areformed of S-ply plywood in which the grain in the outer veneer sheetsforming opposite face plies for each flange extends generallylongitudinally of the beam. It should be understood that the flangesalso may be formed of a plurality of elongated pieces of lumber joinedtogether through adhesively bonded finger joints formed by grooves attheir adjacent sets of ends, similar to those described above joiningthe web sections.

The flanges are secured in face-to-face relationship with one face ofthe web of the beam by being secured thereto, as by adhesive. Althoughthe figures herein illustrate flanges secured only to one face of theweb, it is recognized that in certain instances it may be desirable toprovide a beam having flanges secured to both of its faces, and such isintended to be covered by this disclosure also.

As is illustrated in FIGS. 1 and 2, the joints between adjacent flangesections are offset in a direction longitudinally of the beam from thejoints between adjacent sections of the web. This lends to thecontinuity of strength of the beam along its length. The depth of theweb and the widths of the flanges will be dictated by the length of spanand the loads to be born by the beam.

In use, a beam is supported at its opposite ends on the end walls of amodular housing unit. Roof trusses, such as those illustrated at 50 inFIGS. 1, 2 and 4, are secured to and extend laterally outwardly from thebeam. As illustrated in FIG. 4, an upright leg 52 of a truss is secured,as by nailing, to flanges 22, 24 of the beam. A spacer block 54interposed between leg 52 and web 20 of the beam provides a solidnailing region through which nails or staples can be driven from leg 52into the web of the beam.

A modular housing unit with such a ridge roof beam may be placed againstan adjacent unit with the webs of the beams in face-to-face contact. Thebeams may be bolted together through their flanges to produce anintegral structure.

A modified version of the invention is illustrated in FIG. 5. A beam 16,having a web 20 and flanges 22, 24, may be strengthened, as illustratedin FIG. 5, by securing other flanges, such as those indicated at 58, 60,to those faces of flanges 22, 24 which face outwardly and away from theweb. Flanges 58, 60 are constructed of multiple finger jointed andadhesively bonded together flange sections as previously described forflanges 22, 24 and extend continuously the length of the beam.

As illustrated in FIG. 5 also, the upright leg 52 of a truss 50 may besecured to the face of the web opposite the face to which the flangesare secured. This obviates the need for a block 54 between leg 52 andweb 20 as was required in FIG. 4. The beam still may be secured, as bybolting, to an adjacent beam in a mating housing unit.

A beam, thus constructed, is relatively inexpensive to produce, hasexcellent continuous span strength, and does not add greatly to theweight of the housing unit. For these reasons, it has proven to be adesirable support for roof structures in modular housing units.

While a preferred embodiment of the invention has been described herein,it should be apparent to those skilled in the art that variations andmodifications are possible without departing from the spirit of theinvention.

It is claimed and desired to secure by Letters Patent:

1. A beam comprising an elongated continuous web including a pluralityof elongated plywood web sections joined in end-t0- end relation, eachplywood web section including a pair of outer veneer sheets extendingfully the length of the section with the grain of said outer veneersheets extending generally longitudinally of the beam, and a pluralityof interior veneer sheets therebetween, said veneer sheets beingadhesively bonded together in face-to-face relation along glue linesbetween contiguous sheets, each web section having a groove formed in anend edge thereof receiving an end edge of an adjacent web section, withsaid adjacent web sections being bonded tov gether along said adjacentedges, and

at least a pair of elongated, laterally spaced flanges extendingadjacent and parallel to opposite longitudinal edge margins of said weband secured to at least one face of the web, each of said flangesincluding a plurality of elongated wood flange sections joined inend-to-end relation, each flange section having a groove formed in anend edge thereof receiving an end edge of an adjacent flange section,with said adjacent flange sections being bonded together along saidadjacent end edges.

2. The beam of claim 1, wherein the groove in an end edge of a websection extends lengthwise of said end edge.

3. The beam of claim 1, wherein the groove in an end edge of a flangesection extends lengthwise of said end edge.

4. The beam of claim 1, wherein the flanges are positioned on said webwith the joints between adjacent flange sections offset in a directionlongitudinally of the beam from a joint between adjacent web sections.

5. The beam of claim 1, wherein adjacent end edges of adjacent sectionshave mating complementary groove configurations.

6. The beam of claim 1, wherein the other faces of said outer veneersheets define outer faces for the section, and a grooved end edge of aweb section has a first surface spaced toward the opposite end of thesection from said edge, said first surface extending inwardly from anouter face of one of the outer sheets at a substantial angle relative tosaid face of the sheet and terminating at an inner edge intermediate thefaces of said outer sheet, a second surface extending from the inneredge of the first surface in a plane inclined at a low angle away fromthe outer face of said outer sheet across a glue line between adjacentsheets to the end edge of the section, a third surface disposed towardthe other outer veneer sheet from said second surface, said thirdsurface extending away from said end edge of the section in a planeinclined at a low angle relative to the faces of the section acrossanother glue line in the section to an inner end spaced from said endedge, a fourth surface extending substantially parallel to said secondsurface from said inner end of the third surface to the end edge of thesection, said fourth surface intersecting said end edge in a regionintermediate the faces of the other outer veneer sheet, and a fifthsurface at the end edge of the section extending at a substantial anglerelative to the outer face of the section from the intersection of saidfourth surface with the end edge to the outer face of said outer veneersheet.

7. The beam of claim 1, wherein each flange section includes a pair ofveneer sheets forming opposite face plies of the section and the grainof said sheets extends generally longitudinally of the beam, and theflanges are adhesively bonded to the web with a face ply of each flangesection against an outer face of the web.

8. In a modular housing unit adapted to be joined together along one ofits sides with another housing unit, a ridge roof beam extending alongsaid side of the housing unit, said beam comprising an elongatedcontinuous web including a plurality of elongated plywood web sectionsjoined in end-toend relation, each plywood web section including a pairof outer veneer sheets extending fully the length of the section withthe grain of said outer veneer sheets extending generally longitudinallyof the beam, and a plurality of interior veneer sheets therebetween,said veneer sheets being adhesively bonded together in face-to-facerelationship, each web section having a groove formed in an end edgethereof receiving an end edge of an adjacent web section, with saidadjacent web sections being bonded together along said adjacent edges,and

a pair of elongated, laterally spaced flanges extending adjacent andparallel to opposite longitudinal edge margins of said web and securedto one face of the web, each of said flanges including a plurality ofelongated plywood flange sections joined in end-toend relation, eachflange section having a groove formed in an end edge thereof receivingan end edge of an adjacent flange section, with said adjacent flangesections being bonded together along said adjacent end edges.

9. The housing unit of claim 8, wherein the groove in an end edge of aweb section extends lengthwise of said end edge.

10. The housing unit of claim 8, wherein the groove in and end edge of aflange section extends lengthwise of said end edge.

1 l. The housing unit of claim 10, wherein each flange section includesa pair of veneer sheets forming opposite face plies of the flangesection and the grain of said sheets extends generally longitudinally ofthe beam, and the flanges are adhesively bonded to the web with a faceply of each flange section against an outer face oftheweb.

1. A beam comprising an elongated continuous web including a pluralityof elongated plywood web sections joined in end-to-end relation, eachplywood web section including a pair of outer veneer sheets extendingfully the length of the section with the grain of said outer veneersheets extending generally longitudinally of the beam, and a pluralityof interior veneer sheets therebetween, said veneer sheets beingadhesively bonded together in face-to-face relation along glue linesbetween contiguous sheets, each web section having a groove formed in anend edge thereof receiving an end edge of an adjacent web section, withsaid adjacent web sections being bonded together along said adjacentedges, and at least a pair of elongated, laterally spaced flangesextending adjacent and parallel to opposite longitudinal edge margins ofsaid web and secured to at least one face of the web, each of saidflanges including a plurality of elongated wood flange sections joinedin end-to-end relation, each flange section having a groove formed in anend edge thereof receiving an end edge of an adjacent flange section,with said adjacent flange sections being bonded together along saidadjacent end edges.
 2. The beam of claim 1, wherein the groove in an endedge of a web section extends lengthwise of said end edge.
 3. The beamof claim 1, wherein the groove in an end edge of a flange sectionextends lengthwise of said end edge.
 4. The beam of claim 1, wherein theflanges are positioned on said web with the joints between adjacentflange sections offset in a direction longitudinally of the beam from ajoint between adjacent web sections.
 5. The beam of claim 1, whereinadjacent end edges of adjacent sections have mating complementary grooveconfigurations.
 6. The beam of claim 1, wherein the other faces of saidouter veneer sheets define outer faces for the section, and a groovedend edge of a web section has a first surface spaced toward the oppositeend of the section from said edge, said first surface extending inwardlyfrom an outer face of one of the outer sheets at a substantial anglerelative to said face of the sheet and terminating at an inner edgeintermediate the faces of said outer sheet, a second surface extendingfrom the inner edge of the first surface in a plane inclined at a lowangle away from the outer face of said outer sheet across a glue linebetween adjacent sheets to the end edge of the section, a third surfacedisposed toward the other outer veneer sheet from said second surface,said third surface extending away from said end edge of the section in aplane inclined at a low angle relative to the faces of the sectionacross another glue line in the section to an inner end spaced from saidend edge, a fourth surface extending substantially parallel to saidsecond surface from said inner end of the third surface to the end edgeof the section, said fourth surface intersecting said end edge in aregion intermediate the faces of the other outer veneer sheet, and afifth surface at the end edge of the section extending at a substantialangle relative to the outer face of the section from the intersection ofsaid fourth surface with the end edge to the outer face of said outerveneer sheet.
 7. The beam of claim 1, wherein each flange sectionincludes a pair of veneer sheets forming opposite face plies of thesection and the grain of said sheets extends generally longitudinally ofthe beam, and the flanges are adhesively bonded to the web with a faceply of each flange section against an outer face of the web.
 8. In amodular housing unit adapted to be joined together along one of itssides with another housing unit, a ridge roof beam extending along saidside of the housing unit, said beam comprising an elongated continuousweb including a plurality of elongated plywood web sections joined inend-to-end relation, each plywood web section including a pair of outerveneer sheets extending fully the length of the section with the grainof said outer veneer sheets extending generally longitudinally of thebeam, and a plurality of interior veneer sheets therebetween, saidveneer sheets being adhesively bonded together in face-to-facerelationship, each web section having a groove formed in an end edgethereof receiving an end edge of an adjacent web section, with saidadjacent web sections being bonded together along said adjacent edges,and a pair of elongated, laterally spaced flanges extending adjacent andparallel to opposite longitudinal edge margins of said web and securedto one face of the web, each of said flanges including a plurality ofelongated plywood flange sections joined in end-to-end relation, eachflange section having a groove formed in an end edge thereof receivingan end edge of an adjacent flange section, with said adjacent flangesections being bonded together along said adjacent end edges.
 9. Thehousing unit of claim 8, wherein the groove in an end edge of a websection extends lengthwise of said end edge.
 10. The housing unit ofclaim 8, wherein the groove in and end edge of a flange section extendslengthwise of said end edge.
 11. The housing unit of claim 10, whereineach flange section includes a pair of veneer sheets forming oppositeface plies of the flange section and the grain of said sheets extendsgenerally longitudinally of the beam, and the flanges are adhesivelybonded to the web with a face ply of each flange section against anouter face of the web.